Cash Flow Forecast
Project the balance forward month by month and find the low point — the moment a profitable business can still run out of money.
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How it works
Profit and cash are not the same thing, and the gap between them is what closes businesses. Revenue booked in March may not arrive until June, while payroll and rent leave on schedule regardless.
What matters in a forecast is not the closing balance but the lowest point along the way. A forecast that ends the year comfortably can still dip below zero in month seven, and that dip is the one that needs a facility arranged in advance.
Closing = opening + collections − outflows, each period compounding by its growth rate
- Collection lag — the months between invoicing and the cash arriving
- Trough — the lowest balance across the forecast period
- Closing balance — where the forecast ends — much less important than the trough
Worked example
3,200,000 opening, 2,800,000 monthly inflow growing 6%, 3,100,000 outflow growing 2%, one-month lag
Inputs
Results
The forecast ends 343,000 higher than it began, and still goes 683,600 below zero in month five. Only the month-by-month view catches that.
Frequently asked questions
Why does a profitable business run out of cash?
Because of timing. Costs are paid on schedule while revenue arrives late, and growth makes it worse — every new customer consumes cash for stock, delivery and wages before paying. Fast growth is one of the most common causes of insolvency.
What collection lag should I use?
Your actual average, not your stated payment terms. If terms are 30 days and customers routinely take 55, use two months. The forecast is only as honest as this number.
How far ahead should I forecast?
Twelve months for planning, thirteen weeks in detail if cash is tight. Weekly granularity matters when the trough is close, because a monthly view hides a mid-month payroll gap entirely.
Is my data sent anywhere?
No. The calculation runs entirely in your browser. Nothing you type is transmitted to us or stored.
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